[flows-tinyflows] wiring: output-field and split_out path warnings over a ToolContractLookup port #152

Move OpenHuman's generic wiring checks (flows/ops/wiring_warnings.rs, 338 lines) into tinyflows::wiring behind a host ToolContractLookup port (output_fields, output_schema, primary_array_path, envelope prefix, metadata fields): the binding-to-output-field walk (:92), the data.-envelope check, and the split_out array-path check (:241). Upstream wiring.rs has only schema_says_path_is_non_array today. Expose through Authoring (BuilderFailures or a new warnings member).

Follow migrate-to-submodule (OpenHuman .claude/skills/): upstream PR → patch release → OpenHuman gitlink bump + registry digest re-pin. Design reference: docs/tinyflows-bus-design.md.

Done when: merged in tinyhumansai/tinyflows with wire tests for every new or changed contract type, released (patch), and the contract version bumped where a served shape changed. Gates: cargo fmt --all -- --check, cargo clippy --all-targets --all-features -- -D warnings, cargo test --all-features in tinyhumansai/tinyflows. OpenHuman adoption is a separate leaf of the epic.

Agent brief

• Files to consider (paths in tinyhumansai/tinyflows): crates/tinyflows/src/wiring.rs, crates/tinyflows/src/bindings.rs
• Research: Host wiring_warnings.rs.
• Workflow: an implementing-an-epic step; follow migrate-to-submodule (upstream PR → patch release → OpenHuman gitlink bump + digest re-pin).
• Subagent: tdd-implementer.
• Dependencies: none.

Parent: tinyhumansai/openhuman#8055